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Copyright of Iraqi National Journal of Earth Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Seventeen samples of Hartha Formation in Balad (1) well, central Iraq, are studied on the basis of stratigraphic ranges of the recorded calcareous nannofossils for twenty species belonging to twelve genera. The studied section reveals three biozones arranged from oldest to youngest as follows; (1) Calculites ovalis Interval Biozone (CC19), (2) Ceratolithoides aculeus Interval Biozone (CC20), (3) Quadrum sissinghii Interval Biozone (CC21). These Biozones are correlated with other calcareous nannofossils biozones from both local and regional sections, leading to conclude the age of the Middle Campanian. Rerecorded eighteen ostracode species that belong to eleven genera are identified, all of which were previously recorded from Iraq and adjacent regions. The occurrence of these species leads to conclude a continental shelf environment, while they are typical of inner shelf-outer shelf depth. [ABSTRACT FROM AUTHOR]

Reconstructing intermediate and bottom‐water temperature in the Arctic Ocean is key for understanding paleoclimatic phenomena, such as the region's interactions with warm Atlantic waters, stratification, and sea‐ice dynamics. However, benthic proxy archives are sparse throughout the Arctic circle compared to lower latitudes. Trace‐element ratios (E/Ca) derived from ostracodes, a group of bivalved microscopic crustaceans, have shown promise in this regard. Samples for E/Ca measurements typically require rigorous cleaning prior to analysis, and signs of contamination are routinely monitored through the presence of other trace elements such as Al, Fe, and Mn, which are associated with suspected sources of overprinting. However, there has not yet been an intra‐valve investigation of all of these trace elements, which may hinder our ability to effectively identify geochemical overprinting. Here, we present several elemental concentration and E/Ca ratio measurements in two ostracode genera, Krithe and Polycope, extracted from Chukchi Sea sediment samples. We further investigate the intra‐valve distribution of elements within single shells of adult and juvenile specimens using electron probe microanalysis (EPMA). Our findings suggest that brushing and bleach treatments may not be effective for completely eliminating clays from the edges of valves, which can bias paleoclimatologically relevant trace‐element proxies such as Mg/Ca ratios, particularly in the case of incomplete or small samples with low amounts of calcite material. In addition, we report the first trace‐element data from the genus Polycope, which shows potential as a new Arctic paleotemperature archive. Key Points: Brushing and bleach treatments fail to completely remove external contaminants from valve edges and might compromise E/Ca measurementsIncomplete or juvenile Krithe samples often yield less reproducible E/Ca measurementsPolycope ostracodes show promise for Arctic paleotemperature reconstructions [ABSTRACT FROM AUTHOR]

The Christian Malford lagerstätte in the Oxford Clay Formation of Wiltshire contains exceptionally well-preserved squid-like cephalopods, including Belemnotheutis antiquus (Pearce). Some of these fossils preserve muscle tissue, contents of ink sacks and other soft parts of the squid, including arms with hooks in situ and the head area with statoliths (ear bones) present in life position. The preservation of soft-tissue material is usually taken as an indication of anoxic or dysaerobic conditions on the sea floor and within the enclosing sediments. Interestingly, in the prepared residues of all these sediments there are both statoliths and arm hooks as well as abundant, species-rich, assemblages of both foraminifera and ostracods. Such occurrences appear to be incompatible with an interpretation of potential sea floor anoxia. The mudstones of the Oxford Clay Formation may have been compacted by 70 %–80 % during de-watering and burial, and in such a fine-grained lithology samples collected for microfossil examination probably represent several thousand years and, therefore, a significant number of foraminiferal life cycles. Such samples (even if only 1–2 cm thick) could, potentially, include several oxic–anoxic cycles and, if coupled with compaction, generate the apparent coincidence of well-preserved, soft-bodied, cephalopods and diverse assemblages of benthic foraminifera. [ABSTRACT FROM AUTHOR]

The Mersin Mélange, located in southern Turkey north-west of the city of Mersin, includes blocks and tectonic slices of different origins. The Kilek section in the Mersin Mélange was sampled for a thorough examination of its lithology, biostratigraphy and fossil content. Two samples from the cherty limestone layers within the Huglu Tuffites at the top of the section yielded a rich silicified ostracod fauna of late Early Carnian (based on a two-fold Carnian subdivision) or middle Middle Carnian age (based on a three-fold Carnian subdivision), deposited in an open marine environment, in the outer platform-upper slope zone. We report 121 ostracod species belonging to 53 genera. Two new genera are described: Edithobairdia Forel gen. nov. and Gencella Forel gen. nov., as well as 16 new species: Acanthoscapha mersinella Forel sp. nov., Bairdia hugluensis Forel sp. nov., Acratia kollmanni Forel sp. nov., Citrella? carniana Forel sp. nov., Cytheropteron? schornikovi Forel sp. nov., Eucytherura lacerata Forel sp. nov., Gencella taurensis Forel sp. nov., Kerocythere dorsidenticulata Forel sp. nov., Kerocythere tricostata Forel sp. nov., Monoceratina praevulsaformis Forel sp. nov., Patellacythere tourkosella Forel sp. nov., Polycope kilekensis Forel sp. nov., Ptychobairdia praekristanae Forel sp. nov., Simeonella daginikella Forel sp. nov., Spinomicrocheilinella reliquiaella Forel sp. nov. and Triassocythere tavuscayiriensis Forel sp. nov. The diagnosis of Acratia goemoeryi Kozur is emended. The Kilek fauna retains primitive characteristics illustrated by the first known occurrence of Palaeocopida and Rectonariidae (typical Palaeozoic forms) in the Late Triassic, associated with typical Triassic-modern elements such as thick-shelled and ornamented Bairdiidae and diverse Cytheroidea known from the Middle and Late Triassic worldwide. The unique composition of Palaeozoic and Mesozoic taxa from the Kilek section illustrates unexpected long-term survival in a deep-sea refuge zone following the end-Permian extinction, and the diachronous character of the ostracod recovery in different environments. http://zoobank.org/urn:lsid:zoobank.org.pub:662C3D5C-2B86-4D7B-BDB5-8F8B6A1AD1E7 [ABSTRACT FROM AUTHOR]

Abstract In this report, we describe the first discovery of two living ostracods from the Japanese archipelago, Sinocytheropteron ignobile and Sinocytheridea impressa , which are typically continental faunal elements from China, during our research on the distribution of ostracod assemblages in the Ariake and Yatsushiro Seas in southwest Japan. The (palaeo-) biogeographical data from recent and fossil records indicate that S. ignobile and S. impressa migrated through land bridges during past decreases in sea levels. We also discovered Xestoleberis ryukyuensis , which has been reported from the Ryukyu Islands; its discovery in our study area indicates the current northernmost distribution of the species and suggests that it migrated from the Ryukyu Islands to the study area using the Tsushima Warm Current, a branch of the main Kuroshio Current. This evidence suggests that the migration of shallow-marine ostracods between the continents and their adjacent islands affect not only global oceanic current but also global decreases in sea levels and the (palaeo-) geography of adjacent seas. Thus, ostracods living within the continental coasts provide powerful evidence for reconstructing the connection between the continent and its adjacent islands. Highlights • A total of 155 ostracode species were identified from the Ariake and Yatsushiro Seas. • We discovered living specimens of two Chinese continental taxa. • These Chinese continental taxa do not transported by oceanic current. • The continental taxa living in Japan migrated there during past geological periods. [ABSTRACT FROM AUTHOR]

Considerable research has been done on the Ordovician marine fossils from South China, including macrofossils such as brachiopods, graptolites, bivalves, trilobites, some microfossils like conodonts and acritarches. However, radiolarians and ostracods that are also important constituents of the Ordovician marine ecosystem have been paid little attention in this region. In this study, ten radiolarians species belonging to four genera and sixteen ostracods species grouped into nine genera were found from the Hulo Formation at the Hengdu Section of the Jiangshan District, western Zhejiang Province, South China. The fossil-bearing strata belong to the graptolite Pterograptus elegans Zone which indicates the Late Darriwilian Age. This radiolarian fauna is the first record of the Middle Ordovician radiolarian body fossils and also the earliest Ordovician radiolarian fauna reported from South China. The occurrence of Beothuka in this fauna extends the stratigraphic range of the genus to the Upper Darriwilian. Reviews of previous literatures suggest that the diversity of Beothuka was greater during the Early Ordovician, and then declined gradually from the Early Ordovician to the Middle Ordovician before its extinction. The co-occurring ostracod fauna belongs to a shallow-water ecotype. This is contrary to the host lithofacies of the ostracod fauna which represent a deep-water environment. Therefore, these ostacods may have been transported from the shallow-water environment, most likely from the Yangtze carbonate platform. If this conjecture is the truth, then the Jiangshan District was near the shallow-water carbonate platform and received its sediments during the Darriwilian. It is still essential to do more work in the future to better understand the ecology of the Ordovician ostracod fanuas and their role in the sedimentary system of South China. [ABSTRACT FROM AUTHOR]

The trace element (Sr/Ca and Mg/Ca) and stable isotope (δ 18 O and δ 13 C) geochemistry of fossil ostracod valves provide valuable information, particularly in lacustrine settings, on palaeo-water composition and palaeotemperature. The removal of sedimentary and organic contamination prior to geochemical analysis is essential to avoid bias of the results. Previous stable isotope and trace element work on ostracod shells has, however, employed different treatments for the removal of contamination beyond simple ‘manual’ cleaning using a paint brush and methanol under a low-power binocular microscope. For isotopic work pre-treatments include chemical oxidation, vacuum roasting and plasma ashing, and for trace element work sonication, chemical oxidation and reductive cleaning. The impact of different treatments on the geochemical composition of the valve calcite has not been evaluated in full, and a universal protocol has not been established. Here, a systematic investigation of the cleaning methods is undertaken using specimens of the ubiquitous euryhaline species, Cyprideis torosa. Cleaning methods are evaluated by undertaking paired analyses on a single carapace (comprising two valves); in modern ostracods, whose valves are assumed to be unaltered, the two valves should have identical geochemical and isotopic composition. Hence, when one valve is subjected to the chosen treatment and the other to simple manual cleaning any difference in composition can confidently be assigned to the treatment method. We show that certain cleaning methods have the potential to cause alteration to the geochemical signal, particularly Mg/Ca and δ 18 O, and hence have implications for palaeoenvironmental reconstructions. For trace–element determinations we recommend cleaning by sonication and for stable isotope analysis, oxidation by hydrogen peroxide. These methods remove contamination, yet do not significantly alter the geochemical signal. [ABSTRACT FROM AUTHOR]

The Indonesian Throughflow (ITF) is thought to influence thermohaline circulation dynamics and is important for understanding global climate and the marine ecosystem. The physical and chemical properties of North Pacific Intermediate Water (NPIW) and the underlying deep water incorporated into the ITF appear to be the result of climate-related preconditioning in the North and South Pacific. Thus, these high-latitude source waters play an important role in the Indo-Pacific oceanography. Here, we present the results of down-core faunal analyses of fossil ostracods (Crustacea) that we argue reflect NPIW variability in the central part of the Makassar Strait in the ITF over the past 15 k.y. The results show that the warmwater and low-oxygen-water fauna, and species diversity, rapidly increased at ca. 12 ka, reaching maxima during the Younger Dryas (YD). We interpret the faunal change and the diversity maximum at ca. 12 ka as a response to the stagnation of intermediate water due to the decline in ITF intensity during the YD. After ca. 7 ka, the ostracod faunal composition clearly changed from a relatively shallower, warmer, and low-oxygen fauna to a relatively deeper, colder, and high-oxygen fauna. Our interpretation is that the ostracod fauna was responding to the deglacial-early Holocene sea-level rise and the ventilation variations due to the mixing of the NPIW and the underlying deep water. The intermediate-water environment and the ecosystem in the ITF could have been driven by the intensification of the influence of the underlying deep water, caused by changes in the southern high-latitude source due to the latitudinal displacements of the southwesterly winds. [ABSTRACT FROM AUTHOR]

This research provides the first detailed taxonomic study of Cytherelloidea species from the Aptian deposits of the Kerman area. One hundred and seventy-five samples from two measured stratigraphic sections, Baghin and Siriz, in west and northwest of Kerman, have been analyzed and 11 species identified among them three new species Cytherelloidea baghinensis , Cytherelloidea mazarensis and Cytherelloidea sirizensis are reported for the first time from the regions. The paleoecological aspects of the studied ostracods are discussed as well. A compatible age determination has been inferred through the analysis of benthic foraminifera, gastropoda, pelecypoda and brachiopoda, which have been recovered in the study areas. [ABSTRACT FROM AUTHOR]

The Tiberino Basin is a wide Plio-Pleistocene intermountain basin located in central Apennine (central Italy). Its sedimentary infill is made of a thick succession of Pliocene-early Quaternary continental deposits, the oldest of which can be referred to the Fosso Bianco Formation, composed of grey clays deposited in a huge (at least 500 km²) and relatively deep (not less than 50 m) lake, the Palaeolake Tiberino. We analyse the lacustrine ostracod assemblages from the Fosso Bianco Formation and provide descriptions of five new species included in the subfamily Candoninae (Caspiocypris basilicii sp. nov., Caspiocypris perusia sp. nov., Caspiocypris posteroacuta sp. nov., Caspiocypris tiberina sp. nov. and Caspiocypris tuderis sp. nov.)) and one new species included in the subfamily Limnocytherinae (Paralimnocythere umbra sp. nov.)). The five species of Caspiocypris seem to represent a species flock, i.e. Caspiocypris includes a group of closely related species characterized by monophyly, endemism and speciosity, confirming the 'ancient lake' nature of the Palaeolake Tiberino during the Piacenzian-Gelasian. The ostracod assemblage points to a relatively deep-water and low energy lacustrine environment marked by a high level of endemism. [ABSTRACT FROM AUTHOR]

This work presents a detailed taxonomic study on the marine ostracods from the Paraíba Basin, northeastern Brazil, in wells from the wells Itamaracá-1IT-03-PE and Poty-1PO-01-PE, which record the Maastrichtian–Danian boundary. Besides the taxonomic data, this paper contributes to the paleoenvironmental knowledge of Cretaceous–Paleogene ostracods from the Paraíba Basin. The analysis of 98 samples of the well Itamaracá-1IT-03-PE and 59 samples of the Poty-1PO-01-PE resulted in the record of 34 ostracode species, all representative of a marine environment with normal salinity. Seven new species are proposed: Cytherella centrocompressa sp. nov.; Cytherella paraibensis sp. nov.; Neonesidea potyensis sp. nov.; Bythoceratina spinosa sp. nov.; Eucytherura ventrotuberculata sp. nov.; Langiella fauthi sp. nov. and Protobuntonia punctatum sp. nov. [ABSTRACT FROM AUTHOR]

Members of the ostracod order Palaeocopida, except three very rare genera (Puncia, Manawa and Promanawa), disappeared from the stratigraphical record close to the Permian–Triassic boundary (PTB) event. Species of the genusHollinellaare often present just after the end-Palaeozoic mass extinction event, in latest Permian and earliest Triassic beds. They are among the last representatives of Palaeocopida, the typical Palaeozoic straight dorsal border ostracods. The Early Triassic species have been assigned by most authors toHollinella tingi(Patte, 1935), but this assignment is incorrect. This species is present in the latest Permian and the earliest Triassic, and therefore is considered a biostratigraphical index fossil of the post-mass extinction interval. A revision ofHollinellaspecies from this interval is presented here. ThreeHollinellaspecies occur in the earliest Triassic:H. panxiensisWang, 1978;H. magninodaWang, 1978; andHollinella(Hollinella)lungcamensisCrasquin sp. nov. The new species of the post-PTB event is present in strata exposed in the northern part of Vietnam. All three species ofHollinellacross the PTB andH.(H.)lungcamensisis characteristic of the post-extinction period (latest Changhsingian–earliest Induan). http://zoobank.org/urn:lsid:zoobank.org:pub:C8BA4418-B7FE-4B28-ADA0-28BE317687A4 [ABSTRACT FROM PUBLISHER]

A faunistic survey covering 25 sites in estuaries, coastal lakes and ponds along the west coast of South Africa between the Cape of Good Hope in the south and the Olifants River in the north was carried out in May 2014. The study aimed to establish a dataset with ecological and distribution data of ostracods and foraminifers for later palaeoenvironmental reconstructions. Canonical correspondence analysis showed that the distribution of the 19 foraminifer and 32 ostracod taxa was controlled mainly by habitat structure, but that specific conductivity (salinity) was best and solely described by the second axis, highlighting the usefulness of the two microfossil groups for salinity reconstructions. Habitat structure was demonstrated by the foraminifer speciesTrochamminita irregularis’preference for stillwater areas of lakes.Sarscypridopsis aculeataandSarscypridopsis glabratawere the dominant ostracod species in coastal ponds and lakes. However, their living distributions excluded each other, withS. aculeatapreferring areas of lower salinity andS. glabratadominating areas of higher salinity up to hyperhaline conditions in small, closed water bodies. [ABSTRACT FROM PUBLISHER]

The Cretaceous in the Brazilian Platform records events of magmatism, tectonism and sedimentation coupled to the Gondwana breakup. Some of these events are registered as sedimentary sequences in interior basins, such as in the Cretaceous sequence of the Alto Xingu Sub-basin, Parecis Basin, Central Brazil. This article proposes the faciologic characterization and paleoenvironmental reconstruction of the Cretaceous sequence of the eastern portion of the Parecis Basin and its relation with some reactivated structures as, for instance, the Serra Formosa Arch. Based on both data from outcrops and core drillings a paleoenvironmental and evolutionary reconstruction of the sequence is herein presented. The base of the studied section is characterized by chemical and low energy clastic sedimentation of Lake Bottom and Shoreline, in a context of fast initial subsidence and low sedimentation rate. As the subsidence process decreased, a deltaic progradation became dominant with deposition in a prodelta environment, followed by a deltaic front and deltaic plain interbedded with fluvial plain, and aeolian deposition completing the sequence. The inferred Coniacian–Santonian age is based on vertebrate (fishes and notosuchians) and ostracod fossils with regional chrono-correlates in the Adamantina (Bauru Group), Capacete (Sanfranciscana Basin), and Bajo de la Carpa (Neuquén Group, in Argentina) formations. The formation of a Coniacian depocenter in the Alto Xingu Sub-basin is associated to the Turonian–Coniacian reactivation event in the Peruvian Orogenic Phase of the Andean Orogeny, with the transference of stresses to interplate setting, reactivating Proterozoic structures of the basement. [ABSTRACT FROM AUTHOR]

The calcareous nannofossil Ceratolithus acutus (= C. armatus ) is an important species associated with the final flooding that ended the Messinian Salinity Crisis in the Mediterranean. We emphasize its robust identifying features and stratigraphic value in the global ocean. This species is particularly useful in recognising and constraining the Messinian–Zanclean boundary in the Mediterranean, as evidenced by reports from 75 localities and 20 references in addition to our own papers. Our emphasis is prompted by the assessment of Stoica et al. (2016) that Ceratolithus acutus is a “dubious” species with its lowest occurrence an “unreliable” biostratigraphic event. Such assessments by non-specialists, especially when “supported” by selective referencing of the literature warrant an explanation. [ABSTRACT FROM AUTHOR]

The Lycian nappes lying on top of the para-autochthonous metamorphosed Menderes and unmetamorphosed Bey Dağları successions in SW Anatolia belong to the Tauride segment of the Anatolide-Tauride Block. The Tavas nappe is one of several nappe slices of the Lycian nappes and forms structurally the lowermost tectono-stratigraphic unit. The upper part of the Tavas nappe succession is represented by planktonic foraminifera-bearing uppermost Cretaceous cherty micritic limestones and calciturbidites of the Babadağ Formation and Lower Palaeogene micritic limestones and calciclastic rocks of the Faralya Formation in the study area. Lithostratigraphic characteristics and planktonic foraminiferal assemblages of the two formations in the Bozburun hill locality (S of Köyceğiz) are documented for the first time in three stratigraphic sections in this study. The uppermost part of the Babadağ Formation mainly comprises of alternating calciclastic and micritic limestones, which include diverse planktonic foraminiferal assemblages of mainly keeled morphotypes. The presence of Racemiguembelina fructicosa and Abathomphalus mayaroensis within the assemblages indicates a late Maastrichtian age for the uppermost part of the succession. Two sections of the overlying Faralya Formation comprise mainly planktonic foraminifera-bearing laminated micritic limestones, brecciated limestones and mudstones. Planktonic foraminiferal assemblages of the laminated micritic limestones are dominated by keeled Late Palaeocene morphotypes. The occurrence of Morozovella acuta and Globanomalina planoconica at the base of two sections suggests a Thanetian age for the deposits. The boundary between the Babadağ and Faralya formations is characterized by a stratigraphic gap ranging from the latest Maastrichtian to the earliest Selandian. The gap was linked with the first of the three main events, when ophiolite obduction and incorporation of the Köyceğiz Thrust Sheet into the Lycian allochthon occured. Cretaceous limestone clasts and foraminifers within the Thanetian calciclastic rocks of the Faralya Formation could be clues to that exposure and erosion. [ABSTRACT FROM AUTHOR]

The early Eocene Naredi Formation in the southwestern Kutch represents the initial marine sedimentation in Kutch area during Tertiary period. The 22 m thick succession of Naredi Formation, exposed along cliffs (N 23°34′36.8″, E 68°38′38.1″ and N 23°34′3.1″, E 68°39′7.8″) of the tributary of the Kakdi River in and around Nareda village, is dominantly composed of argillaceous member (also known as gypseous shale member) in the lower part and dominantly biochemically precipitated carbonate member, including newly identified algal and coral reef facies, in the upper part. A total of eight lithofacies have been identified based on sedimentological and micropaleontological attributes; those are alternate green- and brown shale facies, comprising the argillaceous member followed by bioclastic wackestone, Assilina packstone, organically bounded framestone (bioherm), clayey limestone, bioclastic packstone-wackestone alternation and ferruginous coralline limestone in ascending order, which constitute the upper carbonate member. The green as well as brown shale facies are splintery in nature and show horizontal interlamination with gypsum layers. Both these facies contain glauconites with circular to elliptical outline and radial fractures, thus suggesting deposition on a mid- to outer-shelf or restricted lagoonal depositional setting. The overlying horizontally bedded wackestone facies and sparitic packstone facies containing fossil shells of larger benthonic foraminifera, including Assilina spinosa, Assilina and Nummulites burdigalensis with some planktonic forms such as Globigerina and Globorotalia in association to rotalids, ostracods, bivalve and gastropod shells, whose presence depict their deposition in mid- to inner-shelf marine realm under normal seawater salinity. The abundance of peloids, calcispheres and limestone fragments are the major non-biogenic allochems in these facies. Replacement of the ostracods, bivalve and gastropod shells by sparry calcite is also the common feature. The overlying organically bounded algal framestone (bioherm) is characterized by slightly undulatory tabular form in the lower part to concentric undulatory mounds in the upper part showing reef growth at outcrop section whereas framework of curvi-radial concentric growth of carbonate layers under thin section indicates reef formation on shallow marine depositional setting in warm and clear tropical water under normal seawater salinity. The thinly bedded brownish white clayey limestone indicates deposition during deepening of the lagoon. The overlying bioclastic packstone-wackestone alternation facies studded with fragments of algal reef and stromatolitic limestone along with various fossil shells like bivalves, echinoids and gastropods, most of them are micritized, resembles its deposition under back-reef lagoonal environments during storm condition which is overlain by an intertidal coralline limestone deposit showing colonial growth and partial to complete replacement of some of the coral shells by ferruginous mineral along with secondary precipitation of the same within the pores during shallowing of the sea and/or due to late diagenetic changes. Based on shale-carbonate wackestone-packstone-reefal-coralline facies association along with the presence of some key minerals such as glauconite, pyrite, siderite and anhydrite and their genetic link to characteristic depositional milieu, authors have proposed fluctuating depositional environments from lagoonal-barrier ridge to lagoonal-tidal flat for the Naredi Formation. [ABSTRACT FROM AUTHOR]

Assessing the long-term macroevolutionary consequences of sexual selection has been hampered by the difficulty of studying this process in the fossil record. Cytheroid ostracodes offer an excellent system to explore sexual selection in the fossil record because their readily fossilized carapaces are sexually dimorphic. Specifically, males are relatively more elongate than females in this superfamily. This sexual shape difference is thought to arise so that males carapaces can accommodate their very large copulatory apparatus, which can account for up to one-third of body volume. Here we test this widely held explanation for sexual dimorphism in cytheroid ostracodes by correlating investment in male genitalia, a trait in which sexual selection is seen as the main evolutionary driver, with sexual dimorphism of carapace in the genus Cyprideis. We analyzed specimens collected in the field (C. salebrosa, USA; C. torosa, UK) and from collections of the National Museum of Natural History, Washington, DC (C. mexicana). We digitized valve outlines in lateral view to obtain measures of size (valve area) and shape (elongation, measured as length to height ratio), and obtained several dimensions from two components of the hemipenis: the muscular basal capsule, which functions as a sperm pump, and the section that includes the intromittent organ (terminal extension). In addition to the assessment of this primary sexual trait, we also quantified two dimensions of the male secondary sexual trait—where the transformed right walking leg functions as a clasping organ during mating. We also measured linear dimensions from four limbs as indicators of overall (soft-part) body size, and assessed allometry of the soft anatomy. We observed significant correlations in males between valve size, but not elongation, and distinct structural parts of the hemipenis, even after accounting for their shared correlation with overall body size. We also found weak but significant positive correlation between valve elongation and the degree of sexual dimorphism of the walking leg, but only in C. torosa. The correlation between the hemipenis parts, especially basal capsule size and male valve size dimorphism suggests that sexual selection on sperm size, quantity, and/or efficiency of transfer may drive sexual size dimorphism in these species, although we cannot exclude other aspects of sexual and natural selection. [ABSTRACT FROM AUTHOR]

Reconstruction of prehistoric tropical cyclone (TC) activity often relies on the identification of distinctive overwash deposits (tempestites) in coastal lagoon sediments. Similar sediment deposits, however, can result from high-energy events other than TCs. In this study we assessed the utility of using the geochemistry of ostracod valves, specifically their stable oxygen isotope composition (δO), as a potential validation variable that could reduce the chances of misidentifying an overwash deposit as having been generated by a TC, when in fact it formed from another high-energy depositional process (type 1 error). We applied this technique to a sediment core recovered from Laguna Alejandro, Dominican Republic, which had already been analyzed for other sedimentary TC proxies. Negative δO anomalies identified in the ostracod valve stable isotope record are associated with TC deposits and are most easily explained by large influxes of O-depleted meteoric waters typical of intense tropical storms. There is potential for this technique to be used to identify TC landfalls that are not represented by overwash deposits. We, however, propose a more conservative approach and suggest this technique be used to validate the origin of a storm deposit and reduce the odds of a type 1 error. [ABSTRACT FROM AUTHOR]

ABSTRACT The Last Interglacial [LIG, equivalent to marine isotope stage (MIS) 5e] was a period of enhanced global warmth, with potential significance for understanding future climate warming. It has long been proposed that the LIG in Britain (the Ipswichian Interglacial) was significantly warmer than present, based on the occurrence of fossils of extant thermophilous plant and animal species intolerant of the current climate. Here, we review the evidence for palaeotemperatures that can be derived from such fossil taxa (beetles, ostracods, plant macrofossils and herpetiles) to assess the level of warmth that Britain experienced during the LIG. Quantified palaeotemperature reconstructions generated for eight British sequences indicate that the LIG was likely to have been warmer than the present but at only one site (Trafalgar Square) is there strong evidence for climates that were significantly warmer than those experienced during the Holocene. Consequently, while there is evidence to support the idea that the thermal regime of the LIG in Britain was different from that of the Holocene, this evidence is restricted to a single site. The paper concludes by discussing the thermal regime of the LIG in Britain in the context of its role as an analogue for future warming in the 21st century and beyond. [ABSTRACT FROM AUTHOR]

Global climate underwent a period of significant cooling at the Plio–Pleistocene Transition (∼2.6 Ma). The influence of this change on the Kuroshio Current region in the Pacific Ocean, off eastern Asia, is not well known. In this study, we clarify temporal changes in the paleoenvironment under the influence of the Kuroshio Current during the late Pliocene and early Pleistocene using high-resolution faunal proxy records of fossil Ostracoda (Crustacea). The study unit is the Ananai Formation in the southeastern region of Shikoku, southwest Japan. The modern analog technique (MAT) is employed for the quantitative estimation of paleo-bottom water temperatures (PBWTs) and paleo-water depth (PWD) during the deposition of the formation. Ostracode MAT results show PBWT fluctuations during warmest and coldest months, with values of 16°C–20 °C and 12°C–16 °C, respectively, and a PWD of 70–140 m, reflecting sea-level oscillations. Moreover, the PBWT in the coldest month is 3 °C–4 °C lower than present-day water temperatures at the same shallow water depths. Temporal changes in these paleoenvironmental variables based on MAT are in good agreement with global oxygen isotope records. Orbital obliquity cycles with 41-kyr periodicity are recorded for the first time in an onshore section in the Kuroshio Current region at the Plio–Pleistocene boundary interval. [ABSTRACT FROM AUTHOR]

Many micropaleontological studies based on data from on-land sections, oil wells, and deep-sea drilling cores have provided important information about environmental changes in the Japan Sea that are related to the global climate and the local tectonics of the Japanese Islands. Here, major changes in the microfossil assemblages during the Late Pliocene to Early Pleistocene are reviewed. Late Pliocene (3.5-2.7 Ma) surface-water assemblages were characterized mainly by cold-temperate planktonic flora and fauna (nannofossils, diatoms, radiolarians, and planktonic foraminifera), suggesting that nutrient-rich North Pacific surface waters entered the Japan Sea via northern straits. The common occurrence of Pacific-type deep-water radiolarians during this period also suggests that deep water from the North Pacific entered the Japan Sea via the northern straits, indicating a sill depth >500 m. A weak warm-water influence is recognized along the Japanese coast, suggesting a small inflow of warm water via a southern strait. Nannofossil and sublittoral ostracod assemblages record an abrupt cooling event at 2.75 Ma that correlates with the onset of the Northern Hemisphere glaciation. Subsequently, cold intermediate- and deep-water assemblages of ostracods and radiolarians increased in abundance, suggesting active ventilation and the formation of the Japan Sea Proper Water, associated with a strengthened winter monsoon. Pacific-type deep-water radiolarians also disappeared around 2.75 Ma, which is attributed to the intermittent occurrence of deep anoxic environments and limited migration from the North Pacific, resulting from the near-closure or shallowing of the northern strait by a eustatic fall in sea level and tectonic uplift of northeastern Japan. A notable reduction in primary productivity from 2.3 to 1.3 Ma also suggests that the nutrient supply from the North Pacific was restricted by the near-closure of the northern strait. An increase in the abundance of subtropical surface fauna suggests that the inflow of the Tsushima Warm Current into the Japan Sea via a southern strait began at 1.7 Ma. The opening of the southern strait may have occurred after the subsidence of southwestern Japan. [ABSTRACT FROM AUTHOR]

The ostracod fauna of the Aisne quarry section (south-eastern border of the Dinant Synclinorium, Ardenne, Belgium) is studied here in order to complete the Middle Devonian record of these micro-crustaceans on the Ardennean platform, allowing thus biostratigraphic correlations at regional scale. Sixty-four ostracod taxa are recognized throughout the Givetian carbonate sequence of Aisne; one new species ( Cryptophyllus magnei Maillet and Casier n. sp.) is formally described. In the lower part of the section, assemblages contain numerous species that are known to occur as early as the Late Eifelian. The recognized ostracod assemblages and lithostratigraphic correlations with analogous sequences in the Givetian historical type - area (Givet, French Ardenne), which are dated by conodonts, suggest that the sequence of the Aisne quarry is much more expanded. Three acme biozones are established herein for the Givetian stage; they will be useful for both regional (Ardenne area) and supra-regional correlations between the Boulonnais, Ardenne and Eifel areas. The sedimentary palaeoenvironments recorded in the carbonate sequence of the Aisne quarry are reconstructed based on the ostracod faunas. Finally, the biotic response of ostracods to the Taghanic Biocrisis is discussed. [ABSTRACT FROM AUTHOR]

Heterocypris incongruens is a widely distributed ostracod which can maintain its populations under stressful conditions such as those in temporary ponds and under low-quality diets, for example, detritus. It often co-occurs with cladocerans and fish living in shallow water bodies. Nevertheless, little is known about its response to the presence of predators, its consumption capacity of cyanobacteria typically present in eutrophic systems, and its interaction with other species in similar habits. We studied here the demographic responses of H. incongruens fed the green alga Scenedesmus acutus, two strains of microcystis cf. aeruginosa and limnothrix sp. Experiments were conducted separately and together in the presence of the cladoceran Simocephalus vetulus and the cichlid fish, oreochromis kairomones. The ostracod maintained growth in all treatments, the reproductive output decreased on dietary limnothrix sp., and its life expectancy was significantly lower with the toxic strain of microcystis. The coexistence of both crustacean species increased the rate of population growth (~0.33 day-1) of S. vetulus and life expectancy (36-44 days) of H. incongruens on the test diets compared with controls (23-33 days). Our study suggests facilitation affects the interaction between the two microcrustaceans, especially on poor quality cyanobacterial diets. [ABSTRACT FROM AUTHOR]

Abundant isolated specimens of microconchid tubes have been extracted from a microbialite deposit near the Permian- Triassic boundary ( PTB) in the Dajiang section, southern Guizhou Province, South China. They are assignable to Microconchus aff. utahensis, M. aff. aberrans and Helicoconchus aff. elongatus, all of which possess micro-lamellar tube walls. Quantitative analysis of bulk samples indicates that most microconchids occur in the upper part of the PTB microbialite deposit and show substrate selectivity for bioclastic grainstone-packstones. In contrast, very few microconchids were found in the rocks bearing well-developed microbialite structures. Both stratigraphical and substrate preferences indicate proliferation of microconchids coincided with an ebb of microbialite development. Microconchids therefore only proliferated in local niches in which microbial activities were not very active within the PTB microbialite ecosystem. The presence of abundant microconchids further strengthens the impression that PTB microbialite metazoans are much more diverse than previously thought. The end- Permian mass extinction is calibrated to the base of microbialite deposit in South China. Thus, abundant microbialite metazoans, such as ostracods, lingulid brachiopods, microgastropods and microconchids, together with the considerable, temporarily surviving faunas reported from non-microbialite PTB sections in South China, indicate that metazoans diversified immediately after the first episode of the end- Permian mass extinction, supporting the scenario that marine ecosystems underwent episodic collapses during the devastating biocrisis over the Permian- Triassic transition. [ABSTRACT FROM AUTHOR]

The AR-1 layer, corresponding to the Escucha Formation (Lower Cretaceous) in the Santa Maria Mine of Ariño, has supplied rich and well-preserved macrofloral and palynological assemblages showing interesting data about both taphonomic and environmental conditions. This single layer is located in the Oliete Sub-Basin from the Maestrazgo Basin in northeastern Spain, and it represents one of the most outstanding single layer fossil sites in the world. This site shows abundant and diverse fauna containing exquisitely preserved vertebrate and invertebrate fossils (dinosaur bones, turtles, crocodiles, fishes, molluscs and ostracods) and also plant remains of Albian age. The assemblage is especially significant for dinosaur phylogenetic analysis. The sedimentary environment corresponds to a freshwater swamp plain with sporadic marine inputs within a deltaic–estuarine system under subtropical–tropical climate. [ABSTRACT FROM AUTHOR]

The Early Cretaceous ostracod fauna in western Liaoning is divided into eight successive ostracod assemblages. These assemblages have provided information about age constraint of relevant nonmarine Early Cretaceous strata: Yixian Formation - Hauterivian to Barremian, probably up to Aptian; Jiufotang Formation - Barremian to Aptian; Fuxin Formation - Aptian; Sunjiawan Formation - Albian. According to the revised age for the upper part of the Yixian Formation in the Kazuo - Chaoyang Basin, which is Hauterivian - Barremian, Ziziphocypris linchengensis is the earliest record of the genus Ziziphocypris. This work demonstrates that the supra-regionally distributed ostracod species, including species of Cypridea, are useful for biostratigraphic correlation and age determination of lacustrine deposits. In contrast, the endemic Cypridea species are helpful for regional biostratigraphic correlation of scattered basins within western Liaoning. [ABSTRACT FROM AUTHOR]

As a result of detailed comparative-morphological studies of Cyprideis pedashenkoi (Daday 1909), considered by many authors to be synonymous with Cyprideis torosa (Jones 1850), it is now possible to demonstrate that it is a separate species endemic to Lake Issyk-Kul. Morphologically it is no less variable than C. torosa, can be consistently distinguished from that species by its double (vs. V-shaped) frontal muscle scar, the pronounced fossa-mural nature of the surface sculpture, with punctate sculpture grouped into polygonal fields forming a second-order reticulation, as well as by the proportions of some parts of appendage armature and details of the penis structure. [ABSTRACT FROM AUTHOR]

Negative responses of biotic communities as trackers of pollutant dispersion has shown that microfaunal distribution can play a useful role in investigatingmarine coastal ecosystems. A detailed study was carried out on Ostracoda and benthic foraminiferal assemblages from the contaminated environment of the Ex-Military Arsenal of the La Maddalena Harbour, located on the south-eastern coast of LaMaddalena Island (Sardinia, Italy), to investigate the responses to pollution of these micro-organisms in this area using integrated multidisciplinary approaches. The area is affected by industrial waste, mainly heavymetals, as well as by seasonally intensemaritime traffic. The analysis of surficial sediment shows enrichment in pollutants including As, Hg, Zn, Cu, Pd, Cd and hydrocarbon (chain length C>12). Variability of the assemblages, population density, species diversity and frequency of deformity suggest that these microorganisms are promising monitoring groups for contaminated marine areas. Atotal of 28 genera and 42 species of ostracods (three species were found alive; 17 species are autochthonous in at least one sampling station, while 28 are always allochthonous), were collected, while only 9 genera and 16 species of living benthic foraminiferawere recognized. The biocoenosis is poorly represented, and shows low values of biotic indices. On the other hand, the foraminiferal thanatocoenosis is diverse and rich, but a high percentage of abnormal tests indicates degraded environmental conditions in almost the entire area. Changes in biotic indices, presence of tolerant species and development of abnormal tests constitute the main responses of Foraminifera and Ostracoda to pollution in the examined area. [ABSTRACT FROM AUTHOR]

Ostracod assemblages of 52 samples, collected between 15 and 50m water depth on the Southern Tuscany continental shelf (Northern Tyrrhenian Sea), were analysed. Atotal of 68 species and 39 genera was determined. Q-mode cluster analysis performed on the 22most abundant species (>5% in at least one sample) led to identification of clusters (and subclusters) corresponding to four distinct ostracod assemblages. The first assemblage is characterised by the high dominance of Cytheridea neapolitana and is probably linked to an organic matter enrichment, in silty clay bottom; the other three assemblages are more diversified and are dominated, with lower percentages, by species typical of infralittoral and circalittoral environments: C. neapolitana, Cytheropteron ruggierii and Loxoconcha subrugosa assemblage (on silty clay sediments), Pontocythere turbida assemblage (silty sand and silty clay substrates) and Loxoconcha ovulata assemblage (sandy clay and vegetated bottoms). The distribution of ostracod assemblages shows a good correlation with the benthic foraminiferal assemblages founded in the investigated area. Nevertheless, the recognised low diversity can be related to an organic matter enrichment. [ABSTRACT FROM AUTHOR]

The purpose of this study is to collect micropalaeontological evidence concerning the palaeoenvironmental changes that took place at Southern Evoikos Gulf during the Holocene. Southern Evoikos Gulf is a shallow epicontinental basin, at the northern prolongation of the Cycladic Platform (Western Aegean Sea, Greece). The study area of the present research is located at the northern part of this gulf. Two cores,DEH 1 andDEH 5, the sedimentary record of which covers the last 13910 cal. yr B.P., were recovered from 70m and 75.5mwater depth respectively and a detailed quantitative and qualitative ostracod analysis is performed in 88 samples of DEH 5 and 56 samples ofDEH1.Atotal of 45 ostracod specieswere identified fromDEH1 and 52 species fromDEH5. The distribution of ostracod assemblages in the investigated cores indicates that a restricted shallow oligohaline lagoon was formed sometime before 13540 cal yr BPat the northern basin of the Southern Evoikos Gulf. This closed lagoon existed in the area until 11065 cal yr BP. Subsequently, during the Holocene, an unrestricted communication with the sea was established and a marine coastal environment was formed, with a gradual transition (the beginning of which is estimated at about 8000 cal yr BP in DEH 1) from an infralittoral to a circalittoral one. [ABSTRACT FROM AUTHOR]

The study area is located about 40km west ofAydın city in western Turkey and includesNeogene to Quaternary sediments of the Fevzipaşa Formation, which unconformably overlies the Miocene rock units. The Fevzipaşa Formation is composed of conglomerates, sandstones, mudstones, marls, limestones and tuff layers and is unconformably overlain by recent deposits of the Söke-Milet Basin. The lower part of the Fevzipaşa Formation is represented by coarse clastics and lacustrine carbonates followed by fine to coarse-grained sandstones bearing mollusc shells. Prominent tuff layers (lower and upper tuff layers) of this dominantly sandstone succession were radiometrically dated between roughly 2 and 1Ma. Based on small mammal fauna the age of the upper part of the formation is Early to Late Pleistocene. To investigate the paleoenvironmental evolution of the succession, forty-two samples were collected along two stratigraphic sections. Ostracoda assemblages together with Chara flora, Gastropoda and Pelecypoda and fish remains were recovered from only twenty-nine samples. Ostracoda assemblages include Candona neglecta, Cyclocypris ovum, Ilyocypris gibba, I. bradyi, Heterocypris salina and Scottia cf. S. pseudobrowniana. Additionally, fish remains belonging to the Cyprinidae family (Tinca sp., Leuciscus sp. and Leuciscus etilius) and Characeae gyrogonites referable to Nitellopsis obtusa, Chara sp., C. aspera, C. globularis, C. hispida, C. vulgaris, Lychnothamnus sp. and Sphaerochara sp. occurred in the samples. The ostracod, fish, and gyrogonite records all indicate that the Fevzipaşa Formation was deposited in a paleoenvironmental setting characterized by permanent and shallow water bodies. According to the identified Ostracoda assemblages and combining all available stratigraphic data, the age of middle part of the Fevzipaşa Formation is suggested as Early Pleistocene (Calabrian). [ABSTRACT FROM AUTHOR]

The ostracod faunas of six middle to late Eocene sections in the Central Sakarya Region were studied with the aim to describe the palaeoenvironmental changes occurred in the area and the age of the Halidiye Formation. This study based on theOstracoda faunawas carried out for the first time in the region and a comparison between theOstracoda species identified in this study and the data obtained by other previous work carried out in central Europe and Turkey indicated a middle to late Eocene age for the formation. Within the Halidiye Formation, 35 species of Ostracoda belonging to 31 genera were observed, among which, the followings are the more relevant for chronostratigraphic purposes: Cytherella jonesiana (Bosquet), Bairdia cymbulaDeltel, B. crebraDeltel, Neocyprideis williamsoniana (Bosquet), Cuneocythere (Monsmirabilia) triebeli (Keij), Schuleridea perforata (Roemer), Hemicyprideis montosa (Jones ve Sherborn), Cladarocythere apostolescui (Margerie), Krithe parvula Deltel, K. angusta Deltel, K. caudata Van Den Bold, K. rutoti Keij, Trachyleberis aculeata modesta Van Hinte, Pterygocythereis aquitanica Ducasse, Nucleolina multicostata (Deltel), Leguminocythereis genappensis Keij, Grinioneis alata Ducasse, G. paijenborchiana Keij, Quadracythere persica Tambareau, Caudites orientalis Sönmez-Gökçen, Loxoconcha subovata (Muenster), Monoceratina striata Deltel, Uroleberis globosa Ducasse, Paracypris contracta (Jones), Cyprinotus sp., and Heterocypris sp. Based on the lithological properties and environmental indicators, the Halidiye Formation reflects characteristics of transitional lagoonal to deep marine settings. Among the Ostracoda identified hereby, Cyprinotus and Heterocypris indicate freshwater, Cladarocythere, Neocyprideis, and Loxoconcha indicate lagoonal, Leptocythere, Cytheromorpha, and Cyamocytheridea indicate lagoonallittoral, Hermanites, Quadracythere, and Uroleberis indicate epineritic, Monsmirabilia, Schuleridea, and Caudites indicate epineritic-infraneritic, Paracypris indicates infraneritic, Cytherella, Bairdia, and Cytheropteron indicate epineritic-bathyal, and, finally, Krithe and Macrocypris indicate infraneritic-bathyal environmental conditions. [ABSTRACT FROM AUTHOR]

Sinemurian ostracodes from the Lusitanian Basin (western Portugal, Iberian Peninsula) were studied using twelve samples from the marl-limestone succession of the Coimbra Formation at S. Pedro de Moel, north of Lisbon. The detailed taxonomical study identified 11 genera and 14 species, among which 3 are new species: Phraterfabanella boomeri Cabral and Colin n. sp., Klieana? coimbraensis Cabral and Colin n. sp. and "Klinglerella" roselinae Cabral and Colin n. sp.. The recognized ostracode species are particularly similar to those described from the uppermostHettangian-Sinemurian offshore Southwest Ireland (Fastnet Basin) and France (Normandy, Central France and Quercy). Overall, the assemblages include four brackish species (one clearly dominant) and ten marine species. The paleoecological analysis of the assemblages allowed a detailed paleoenvironmental reconstruction, reflecting frequent variations from brackish to restricted marine to slightly more open marine settings, which is supported by sedimentological and other paleontological data. [ABSTRACT FROM AUTHOR]

Paleoecological analyses are important tools for the reconstruction of paleoenvironments. This paper had the objective of using analysis of ostracode assemblages and carbonate microfacies of a well (Carbomil) and an outcrop (Quixeré) from the Jandaíra Formation, Potiguar Basin, in order to verify how they corroborate and complement the other. Two paleoenvironments for Carbomil Well (assemblages 1 and 2, respectively marine and brackish to neritic environments) and one for Quixeré Outcrop (assemblage 3, marine environment) were identified through the ostracode assemblage analysis. Thin section analysis allowed the identification of two different facies for Carbomil Well, i.e. bioclastic packstones to wackstones, a marine brackish or restricted marine system; and bioclastic grainstones to packstones, a normal, shallow marine system. High levels of alteration on the samples prevented an adequate analysis of Quixeré Outcrop; however, it seems to point towards a low-energy environment. Overall, information provided by the thin sections corroborate and complement data of the ostracode assemblages, which allowed a higher degree of certainty for the paleoenvironmental analysis. [ABSTRACT FROM AUTHOR]

Most of the cities built by the Mayas in the Petén area, in the Central Yucatán Peninsula, were abandoned 1200 to 1000 years ago. The phenomenon is sometimes un-appropriately called “the collapse of the Maya civilization”. Its main causes are still debated, ranging from climatic according to the occurrence of severe or modest droughts, to societal in the form of environmental mismanagement of the environment. In both processes, it is inferred that stress triggered the formation in many Petén lake sediments of erosional clay deposits, known as ’Maya clays’. This work presents a high resolution, multi-proxy study of ’Maya clays’ in lacustrine sediments from Laguna Tuspán, near the archaeological site of La Joyanca. Micropaleontological (ostracodes), mineralogical (clay minerals) and geochemical (bulk elemental composition and stable isotopes in organic carbon) records reveal three different phases of soil erosion throughout the last 5300 years. The oldest phase from 5281 to 2998 cal yr BP (i.e. 3331 - 1048 BC) is characterized by successive natural and moderate soil erosion deposits which follow climatic variations recorded in the American tropical belt. The time interval between 2998 and 1281 cal yr BP (i.e. 1048 BC and AD 661) contains four distinct erosional layers which, according to clay mineralogy, are indicative of both increased erosion of the regolith and strong soil loss. The most recent, also the most massive, deposit of Maya clay ends around 1281 cal yr BP (AD 661), that is some 200 years before the so-called ’Maya collapse’ in the Petén area. Recent archeological fieldwork studies indicate that a population mobility took place into the city of La Joyanca from its hinterland by the early Late Classic Period (ca. AD 600), that is, at the end or just after this erosion episode, and well before the occurrence of the Terminal Classic-Postclassic (AD 800-1250) drastic climatic changes. Shifts in environmental management by the local society and timing of urbanization may explain environmental changes better than droughts per se. [ABSTRACT FROM AUTHOR]

During recent years, geo-archaeology has been revitalised and much effort has been made to combine geo-archaeological sciences like geomorphology, sedimentology, micropalaeontology and geochemistry with the cultural archaeological approach. The first definition of geo-archaeology dates back to the late seventies and since then has evolved to include more and more multidisciplinary studies. In this perspective, ostracods play a crucial role since they are valuable palaeoenvironmental indicators in all aquatic habitats, from freshwater to marine. Despite their potential, the integration of ostracods in archaeological studies has not been immediate. Only in the nineties did ostracod geo-archaeology seem to finally take its place, including a systematic approach to ostracod studies in archaeological excavations. Since then, many geo-archaeological investigations have included ostracod analyses, exploiting their potential as multitask tools. The research papers composing this special issue, demonstrate that ostracods can be used in the most diverse settings as tracers of archaeological material provenance, proxies for palaeoenvironmental and palaeoclimate reconstructions as well as clues to human impact. [ABSTRACT FROM AUTHOR]

We present ostracod data from the Middle Palaeolithic open air site of Nahal Mahanayeem Outlet (NMO) at the southern edge of the Hula Basin, northern Israel. Sediments of two Pleistocene water bodies are exposed at the site. The first one is an archaeologically sterile, light-colored limnic carbonate with an Early Pleistocene age. It contains an ostracod fauna assemblage dominated by Candona neglecta , Candonopsis kingsleii , and Pseudocandona sp., and, in minor abundances, Cypria ophtalmica , Cyprideis sp., Humphcypris sp., Fabaeformiscandona cf. fabaeformis and Ilyocypris sp. These sediments were deposited in a shallow, freshwater to oligohaline lake under stable conditions. Sediments of the second water body are silty and dark-colored with a depositional age of 65 ka, belonging to the Late Pleistocene Ashmura Formation. The unit covers a geologically complex topography of tectonically uplifted limnic deposits and a hill-like gravel bar at the site. The most important archaeological layer is situated at its base, containing a lithic assemblage ascribed primarily to the Middle Palaeolithic Mousterian tradition and very well preserved flora and fauna. In the sediments from the archaeological layers, the brackish water ostracod Cyprideis torosa and the foraminifer Ammonia tepida could be identified. In sediments of the Ashmura Formation taken near the site, C. neglecta , Candona angulata , Ilyocypris sp., C. kingsleii , Pseudocandona sp., C. ophtalmica , Darwinula stevensoni , Trajancypris sp. and Potamocypris smaragdina were found, indicating a freshwater to slightly oligohaline stagnant water body. The ostracod fauna of the NMO site, together with geochemical data, allow us to reconstruct a depositional environment of the margin at a shallow lake with brackish or saline springs nearby during the site's occupation by Middle Palaeolithic humans. Additionally, Candona weltneri , Candona cf. meerfeldiana , C. kingsleii , Cyclocypris laevis , C. ophtalmica , Cyprideis sp., Fabaeformiscandona cf. fabaeformis , P. smaragdina , Pseudocandona depressa , Trajancypris sp, Zonocypris cf. costata and A. tepida could be recorded for the first time for the Pleistocene limnic strata of the Hula Basin. [ABSTRACT FROM AUTHOR]

A rich microbiota with distinctive plant fossils has been discovered in Type A morphotype coprolites from the Lameta Formation of Pisdura, in Maharashtra, India. Macerated fractions examined with scanning electron microscopy revealed seven ostracod taxa, ( ?Mongolianella sp., Cypridea ( Pseudocypridina ) sp., Cypridopsis sp., Eucypris sp., Gomphocythere sp., Gomphocythere paucisulcatus , and Paracypretta sp.), diatoms ( Aulacoseira sp.), a charophyte ( Microchara sp.), and sponge spicules. Abundant probable chrysophytes were also observed in thin sections of one of the coprolites. Most of the plant debris is unidentifiable, but recognizable tissues include gymnosperm tissues, a spore, cuticle, and leaf laminae replaced with silica. Chemical analyses reveal that the coprolites are phosphatic, with ~ 12.2 to 16.2 wt.% phosphorus. The microfossils support a Maastrichtian age and fluvio-lacustrine depositional conditions for the Lameta Formation at Pisdura. The unusual combination of a phosphatic composition with plant and microfossil dietary residues suggests that the ancient faecal producers were intentional or inadvertent omnivores. [ABSTRACT FROM AUTHOR]

The Mg/Ca of calcite from the marine ostracod genus Krithe may be an important tool for reconstructing past changes in oceanic bottom water (150-4000 m water depth) temperature. Rigorous cleaning procedures, routinely used to remove clays, organic matter and Fe-Mn oxyhydroxide coatings in trace element studies of foraminifera, are not regularly applied to marine ostracods despite the potential for Mg contamination. Here we apply standard oxidative and reductive foraminiferal cleaning procedures to core top Krithe pernoides valves from boxcore OCE205-50BC (26.23ºN, 77.7ºW, 817 m water depth) to evaluate the effects of contamination on Mg/Ca ratios and assess the impact of cleaning techniques on contaminant removal and ostracod valve chemistry. Our results show that clays and Fe-Mn oxyhydroxides influence the Mg/Ca of Krithe. Following sonication in methanol/ultrapure water, there is a 1.6 mmol/mol (11%) decrease in Mg/Ca (equivalent to a reduction in reconstructed temperature of 1.5 ºC), indicating that this is a critical step in the preparation of Krithe valves for Mg/Ca analyses. Oxidation with buffered hydrogen peroxide has little effect on the Mg/Ca of valves from our site. Reductive cleaning reduces inter-valve variability from 12% to 5%, resulting in an equivalent temperature precision of ± 0.6 ºC. However, reductive cleaning also decreases Mg/Ca ratios due to the partial dissolution of the valve surface. Reductive cleaning offers the potential to improve Krithe Mg/Ca paleotemperature reconstructions and should be utilised in future Krithe Mg/Ca studies. Future work should also aim to constrain the effects of partial dissolution of the valve surface. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the authors discuss various reports within the issue on topics including the development of relational database on marine ostracods, the taxonomy of fossil ostracod, and the species of the genus Bathyconchoecia in southern South China Sea.

The non-marine Lower Cretaceous ostracod genus Kegelina new genus (Cypridoidea, Cyprideidae) is known from South America (Bahia state, eastern Brazil), West Africa (Gabon and 'Congo'), and North America (Montana, Idaho and Wyoming, U.S.A.). It comprises five species: Kegelina anomala (Peck, 1941) new combination, Kegelina armata (Krömmelbein, 1962) new combination, Kegelina bisculpturata (Wicher, 1959) new combination, Kegelina depressa (Moura, 1972) new combination, and Kegelina kegeli (Wicher, 1959) new combination, all of which having formerly been described as representatives of Cypridea Bosquet, 1852. The closer relationships of Kegelina new genus among the Cyprideidae Martin, 1940 are discussed. Other potential species of Kegelina n. gen. are presumed to occur in northeastern China and Europe but remain to be examined [ABSTRACT FROM AUTHOR]

Here we record the occurrence of a new species of the Herefordshire Lagerstätte ostracod genus Pauline from the Lower Silurian (upper Telychian) of North Greenland. Pauline nivisis sp. nov. was recovered from a limestone boulder (Pentamerus Bjerge Formation) collected south of Kap Schuchert, Washington Land. It is reasonable to transpose the palaeobiology known from the Herefordshire Pauline avibella – body, limbs including swimming antennae, lateral eyes, gills and alimentary system – into the carapace of the Greenland species, which represents the oldest cylindroleberidid myodocopid and almost the oldest known myodocope, and is the first record of a Herefordshire Lagerstätte genus from outside the Welsh Borderland locality. Morphological, sedimentological and faunal evidence suggest that the Greenland species was nektobenthic. This is compatible with the notion that ostracods (specifically myodocopids) did not invade the water column until later in the Silurian, in the Wenlock and Ludlow epochs. Pauline is an Early Silurian link between ‘Baltic-British’ and North Laurentian ostracod faunas, endorsing the idea that the UK and Greenland were in close geographical proximity, near a remnant Iapetus Ocean, during late Llandovery time. [ABSTRACT FROM PUBLISHER]

The new genus Tanycythere (Crustacea, Ostracoda) is described from the Jurassic (Hettangian-Bathonian) of western and central Europe based on T. caudata new species, T. praecaudata praecaudata new subspecies, T. praecaudata parallela new subspecies, T. duartei new species, T. posteroelongata new species, and T. wattonensis new species. Another new species, T. procera, is described from the Lower Cretaceous (?Barremian). Recognition of a new genus comprising six new species and subspecies indicates that overall Jurassic and Early Cretaceous ostracod biodiversity is underestimated. [ABSTRACT FROM AUTHOR]

Abstract: A comprehensive multi-proxy study of mini-core Ash-2009-08 from the inner shelf of the northeastern Black Sea, allowed us to define recent environmental changes in the area, on a sub-decadal resolution. The age model of the core based on radionuclide (210Pb and 137Cs) measurements suggests an average sedimentation rate of 2 mm/y and, consequently, a sedimentary record spanning the last ∼140 years. Overall, four fossil groups studied from the core indicate subtle environmental changes. The dinocyst assemblages show stable surface water conditions with a possible cooling in the 1930s-1950s and a slight decline in salinity from the 1960s, which corresponds to an increase in precipitation and the fresh water balance of the Black Sea, known from the published instrumental data. A gradually increasing abundance of the heterotroph species suggests a nutrient increase from the 1920s. Ostracods and molluscs demonstrate rather stable bottom-water salinity and biotopes over the last ∼75 years. Changes in abundance of ostracods and benthic foraminifers, as well as changes in the mollusc diversity, most likely reflect variations in trophic conditions with the higher food supply to the sea floor in the 1940s–1960s and from the late 1990s. Enhanced bottom-water energy is inferred from the mollusc enrichment and a relatively high content of the fine sand grain-size fraction in the 1990s. In the pollen assemblages, trees mainly represented by Pinus strongly prevail over herbs throughout the record. However, the trees to herbs ratio demonstrates a slight decline from the 1920s, most likely resulting from human impact on the vegetation of the nearby land. [Copyright &y& Elsevier]

Abstract: Knowledge of the synchronicity and discrepancy of temperature variations along the Eastern margin of the Tibetan Plateau (ETP) is critical in understanding the driving forcing of regional temperature variations. In this study, we established δ15N timeseries in organic matter and δ13C timeseries in ostracod shells from sediments of Lake Lugu and attributed their variations to decadal/multi-decadal temperature variations. We compared temperature variations along the ETP transect during the past four centuries based on our presently developed and previously developed temperature proxy indices, as well as temperature variations reconstructed by other researchers. We found that: (1) Over the north ETP area (N-ETP), the decadal/multi-decadal variations in temperature correlate well with each other. (2) Over the south ETP area (S-ETP), temperature variations correlate not so well with each other; while those at south to west portion of the Tibetan Plateau are rather local. (3) The decadal variations in temperature are generally synchronous with those in precipitation over the N-ETP area, and they are broadly anti-phase/out-of-phase with the corresponding ones over the S-ETP area. (4) The long term temperature and precipitation trends are coupling over the N-ETP but decoupling over the S-ETP. We speculate that because the N-ETP is located at the frontier of the Asian summer monsoon (ASM) region, temperature variations there are not as strongly influenced by the ASM; they are most likely dominated by changes in solar activities, and show general similarity to the average of the Northern Hemisphere. Over the S-ETP area, decadal temperature variations are obviously influenced by precipitation. Because the decadal/multi-decadal precipitation variations are anti-phase and/or out-of-phase between the N-ETP and S-ETP, the decadal/multi-decadal temperature variations between these two regions are also anti-phase and/or out-of-phase. [Copyright &y& Elsevier]

Summary: Ostracod crustaceans are the most abundant fossil arthropods and are characterized by a long stratigraphic range. However, their soft parts are very rarely preserved, and the presence of ostracods in rocks older than the Silurian period [1–5] was hitherto based on the occurrence of their supposed shells. Pyritized ostracods that preserve limbs and in situ embryos, including an egg within an ovary and possible hatched individuals, are here described from rocks of the Upper Ordovician Katian Stage Lorraine Group of New York State, including examples from the famous Beecher’s Trilobite Bed [6, 7]. This discovery extends our knowledge of the paleobiology of ostracods by some 25 million years and provides the first unequivocal demonstration of ostracods in the Ordovician period, including the oldest known myodocope, Luprisca incuba gen. et sp. nov. It also provides conclusive evidence of a developmental brood-care strategy conserved within Ostracoda for at least 450 million years. [ABSTRACT FROM AUTHOR]